Inductor for single-shot induction heating of complex workpieces

Abstract

A single-shot inductor is provided to induction heat treat a complex workpiece that has an at least partially cylindrical component with its central axis coincident with the central axis of a circular component and connected at one end to the circular component with a diameter larger than the diameter of the at least partially cylindrical component. The single-shot inductor has a single crossover inductor section connected to the first ends of two longitudinal leg inductor sections with the second ends of the two longitudinal leg inductor sections connected to a collar inductor section that surrounds the entire circumference of the at least partially cylindrical component when the complex workpiece is loaded in the single-shot one-turn inductor for an induction heating application. Alternatively the single-shot inductor may have two collar inductor sections interconnected between two longitudinal leg inductor sections where one of the leg sections can accept a supply of alternating current.

The invention claimed is: 
     
       1. A single-shot inductor for an induction heat treatment of a complex workpiece comprising an at least partially cylindrical component with its central axis coincident with the central axis of a circular component, the at least partially cylindrical component connected at one end to the circular component and the circular component having a circular component diameter larger than a cylindrical component diameter of the at least partially cylindrical component, the single-shot inductor comprising:
 a crossover inductor section, the crossover inductor section comprising a supply crossover section and a return crossover section, the supply crossover section having a power source supply end and a supply leg crossover section end, the supply leg crossover section end opposing the power source supply end, the return crossover section having a power source return end and a return leg crossover section end, the return leg crossover section end opposing the power source return end, the supply crossover section and the return crossover section electrically isolated from each other between the power source supply end and the power source return end, the power source supply end and the power source return end located adjacent to each other and separated by a dielectric; 
 a collar inductor section, the collar inductor section comprising a first collar section and a second collar section, the first collar section having a first collar section supply leg end and a first collar section return leg end, the first collar section return leg end opposing the first collar section supply leg end, the second collar section having a second collar section supply leg end and a second collar section return leg end, the second collar section return leg end opposing the second collar section supply leg end; 
 a supply longitudinal leg inductor section having a supply leg crossover end and a supply leg collar end, the supply leg collar end opposing the supply leg crossover end, the supply leg crossover end connected to the supply leg crossover section end, and the supply leg collar end connected between the first collar section supply leg end and the second collar section supply leg end; and 
 a return longitudinal leg inductor section having a return leg crossover end and a return leg collar end, the return leg collar end opposing the return leg crossover end, the return leg crossover end connected to the return leg crossover section end, and the return leg collar end connected between the first collar section return leg end and the second collar section return leg end to form a continuous electrical conductor from the first collar section and the second collar section around the supply leg collar end of the supply longitudinal leg inductor section and the return leg collar end of the return longitudinal leg inductor section whereby when the at least partially cylindrical component of the complex workpiece is situated between the supply longitudinal leg inductor section and the return longitudinal leg inductor section and the circular component is situated adjacent to the exterior face of the collar inductor section, and an alternating current power source is connected between the power source supply end of the supply crossover section and the power source return end of the return crossover section, the complex workpiece is inductively heat treated. 
 
     
     
       2. The single-shot inductor of  claim 1  wherein:
 the crossover inductor section is generally semicylindrical in shape, and the supply crossover section and the return crossover section are each generally quarter-cylindrical in shape; 
 the collar inductor section is generally an annular cylindrical ring in shape, and the first collar section and the second collar section are each generally annular semicylindrical rings in shape and of equal arcuate length; and 
 the supply longitudinal leg inductor section and the return longitudinal leg inductor section are generally perpendicularly oriented in length to a radial plane of the crossover inductor section and the collar inductor section. 
 
     
     
       3. The single-shot inductor of  claim 1  wherein the supply crossover section and the return crossover section are non-coplanar to each other. 
     
     
       4. The single-shot inductor of  claim 1  further comprising at least one profiled region in at least one of the supply crossover section, the return crossover section, the supply longitudinal leg inductor section, the return longitudinal leg inductor section, the first collar section or the second collar section. 
     
     
       5. The single-shot inductor of  claim 4  wherein the at least one profiled region comprises a stepped profile region. 
     
     
       6. The single-shot inductor of  claim 1  further comprising at least one internal cooling circuit formed within the crossover inductor section, the supply longitudinal leg inductor section, the return longitudinal leg inductor section and the collar inductor section for flowing a cooling medium within the at least one internal cooling circuit. 
     
     
       7. The single-shot inductor of  claim 1  further comprising;
 a first cooling circuit comprising:
 a first cooling circuit supply inlet port in communication with a first collar section internal cooling passage in the first collar section; 
 a return longitudinal leg inductor section internal cooling passage in the return longitudinal leg inductor section in communication with the first collar section internal cooling passage; 
 an return crossover section internal cooling passage in the return crossover section in communication with the return longitudinal leg inductor section internal cooling passage; and 
 a first cooling circuit return outlet port in communication with the return crossover section internal cooling passage whereby a cooling medium flows sequentially through the first collar section, the return longitudinal leg inductor section and the return crossover section; 
 and 
 
 a second cooling circuit comprising:
 a second cooling circuit supply inlet port in communication with a second collar section internal cooling passage in the second collar section; 
 a supply longitudinal leg inductor section internal cooling passage in the supply longitudinal leg inductor section in communication with the second collar section internal cooling passage; 
 a supply crossover section internal cooling passage in the supply crossover section in communication with the supply longitudinal leg inductor section internal cooling passage; and 
 a second cooling circuit return outlet port in communication with the supply crossover section internal cooling passage whereby the cooling medium flows sequentially through the second collar section, the supply longitudinal leg inductor section and the supply crossover section. 
 
 
     
     
       8. A single-shot inductor for an inductor heat treatment of a complex workpiece comprising an at least partially cylindrical component with its central axis coincident with the central axis of a circular component, the at least partially cylindrical component connected at one end to the circular component and the circular component having a circular component diameter larger than a cylindrical component diameter of the at least partially cylindrical component, the single-shot inductor comprising:
 a top collar inductor section, the top collar inductor section comprising a top collar first section and a top collar second section, the top collar first section having a top collar first section first leg end and a top collar first section second leg end, the top collar first section second leg end opposing the top collar first section first leg end, the top collar second section having a top collar second section first leg end and a top collar second section second leg end, the top collar second section second leg end opposing the top collar second section first leg end; 
 a bottom collar inductor section, the bottom collar inductor section comprising a bottom collar first section and a bottom collar second section, the bottom collar first section having a bottom collar first section first leg end and a bottom collar first section second leg end, the bottom collar first section second leg end opposing the bottom collar first section first leg end, the bottom collar second section having a bottom collar second section first leg end and a bottom collar second section second leg end, the bottom collar second section second leg end opposing the bottom collar second section first leg end; 
 a power supply longitudinal leg inductor section having a power supply longitudinal leg top collar section end and a power supply longitudinal leg bottom collar section end, a power source supply terminal and a power source return terminal disposed between the power supply longitudinal leg top collar section end and the power supply longitudinal leg bottom collar section end, the power source supply terminal and the power source return terminal electrically isolated from each other, the power supply longitudinal leg top collar section end connected to the top collar first section first leg end and the top collar second section first leg end, and the power supply longitudinal leg bottom collar section end connected to the bottom collar first section first leg end and the bottom collar second section first leg end; and 
 a return longitudinal leg inductor section having a return longitudinal leg top collar section end and a return longitudinal leg bottom collar section end, the return longitudinal leg bottom collar section end opposing the return longitudinal leg top collar section end, the return longitudinal leg top collar section end connected to the top collar first section second leg end and the top collar second section second leg end, and the return longitudinal leg bottom collar section end connected to the bottom collar first section second leg end and the bottom collar second section second leg end, whereby when the complex workpiece is loaded in the single-shot inductor, the at least partially cylindrical component is situated between the power supply longitudinal leg inductor section and the return longitudinal leg inductor section and the circular component is situated adjacent to the exterior face of the bottom collar inductor section, and an alternating current power source is connected between the power source supply terminal and the power source return terminal, the complex workpiece is inductively heat treated. 
 
     
     
       9. The single-shot inductor of  claim 8  wherein:
 the top collar inductor section and the bottom collar inductor section are each generally an annular cylindrical ring in shape; the top collar first section and the top collar second section are each generally annular semicylindrical rings in shape and of equal arcuate length; and the bottom collar first section and the bottom collar second section are each generally annular semicylindrical rings in shape and of equal arcuate length; and 
 the power supply longitudinal leg inductor section and the return longitudinal leg inductor section are generally perpendicularly oriented in length to a radial plane of the top collar inductor section and the bottom collar inductor section. 
 
     
     
       10. The single-shot inductor of  claim 8  wherein the distance between the power source supply terminal and the power supply longitudinal leg top collar section end is not equal to the distance between the power source return terminal and the power supply longitudinal leg bottom collar section end. 
     
     
       11. The single-shot inductor of  claim 8  further comprising at least one profiled region in at least one of the top collar inductor section, the bottom collar inductor section, the power supply longitudinal leg inductor section or the return longitudinal leg inductor section. 
     
     
       12. The single-shot inductor of  claim 11  wherein the at least one profiled region comprises a stepped profile region. 
     
     
       13. The single-shot inductor of  claim 8  further comprising at least one or more internal cooling circuits formed within the top collar inductor section, the power supply longitudinal leg inductor section, the return longitudinal leg inductor section, and the bottom collar inductor section for flowing a cooling medium within the at least one or more internal cooling circuits. 
     
     
       14. A method of single-shot induction heat treatment of a complex workpiece comprising an at least partially cylindrical component with its central axis coincident with the central axis of a circular component, the at least partially cylindrical component connected at one end to the circular component and the circular component having a circular component diameter larger than a cylindrical component diameter of the at least partially cylindrical component, with a heat treatment inductor comprising: a crossover inductor section, the crossover inductor section comprising a supply crossover section and a return crossover section, the supply crossover section having a power source supply end and a supply leg crossover section end, the supply leg crossover section end opposing the power source supply end, the return crossover section having a power source return end and a return leg crossover section end, the return leg crossover section end opposing the power source return end, the supply crossover section and the return crossover section electrically isolated from each other between the power source supply end and the power source return end, the power source supply end and the power source return end located adjacent to each other and separated by a dielectric; a collar inductor section, the collar inductor section comprising a first collar section and a second collar section, the first collar section having a first collar section supply leg end and a first collar section return leg end, the first collar section return leg end opposing the first collar section supply leg end, the second collar section having a second collar section supply leg end and a second collar section return leg end, the second collar section return leg end opposing the second collar section supply leg end; a supply longitudinal leg inductor section having a supply leg crossover end and a supply leg collar end, the supply leg collar end opposing the supply leg crossover end, the supply leg crossover end connected to the supply leg crossover section end, and the supply leg collar end connected between the first collar section supply leg end and the second collar section supply leg end; and a return longitudinal leg inductor section having a return leg crossover end and a return leg collar end, the return leg collar end opposing the return leg crossover end, the return leg crossover end connected to the return leg crossover section end, and the return leg collar end connected between the first collar section return leg end and the second collar section return leg end to form a continuous electrical conductor from the first collar section and the second collar section around the supply leg collar end of the supply longitudinal leg inductor section and the return leg collar end of the return longitudinal leg inductor section, the method comprising:
 loading the at least partially cylindrical component of the complex workpiece between the supply longitudinal leg inductor section and the return longitudinal leg inductor section so that the circular component is situated adjacent to the exterior face of the collar inductor section of the heat treatment inductor; 
 supplying an alternating current between the power source supply end of the supply crossover section and the power source return end of the return crossover section to inductively heat treat the complex workpiece; and 
 unloading the complex workpiece from the heat treatment inductor. 
 
     
     
       15. The method of  claim 14  further comprising rotating the complex workpiece about the central axis of the complex workpiece while at least part of a time period when supplying the alternating current between the power source supply end of the supply crossover section and the power source return end of the return crossover section.